Air filter system

ABSTRACT

A SYSTEM FOR FILTERING AND CLEANING AIR OR GAS STREAMS, WHEREIN AND ENDLESS FORAMINOUS BELT IS TRAINED OVER SPACEDAPART ROLLERS, INCLUDING A DRIVE ROLLER HAVING BRISTLE-TYPE BELT-ENGAGING ELEMENTS AND IS MOVED ACROSS THE PATH OF FLOW OF AN AIR OR GAS STREAM BY MEANS OF A WATER-DRIVEN TURBINE HAVING ITS DRIVE SHAFT CONNECTED TO THE DRIVE ROLLER AND HAVING ITS WATER EXHAUST STREAM DIRECTED TO EFFECT WASHING OF PARTICULATE MATTER FROM THE BELT.

AIR FILTER SYSTEM 2 Sheets-Sheet 1 Filed July 9, 1971 E. F. OSBORNE, JR.

INVENTOR.

ATTORNEY Feb. 27, 1973 E. F. OSBORNE. JR 3,717,973

AIR FILTER SYSTEM Filed July 9, 1971 2 Sheets-Sheet 2 .7. 7 v 7 7 E.f-'.OSBORNE, JR.

INVENTOR.

ATTORNEY United States Patent O 3,717,978 AIF FILTER SYSTEM Edwin F.Osborne, Jr., 402 Ripple Creek, Houston, Tex. 77024 Filed July 9, 1971,Ser. No. 161,083 Int. Cl. B01d 46/18 US. Cl. 55-242 Claims ABSTRACT OFTHE DISCLOSURE A system for filtering and cleaning air or gas streams,wherein an endless foraminous belt is trained over spacedapart rollers,including a drive roller having bristle-type belt-engaging elements andis moved across the path of flow of an air or gas stream by means of awater-driven turbine having its drive shaft connected to the driveroller and having its water exhaust stream directed to effect washing ofparticulate matter from the belt.

BACKGROUND OF THE INVENTION DESCRIPTION OF THE INVENTION The presentinvention is directed to improvements in the moving-belt type of airfilter by which the same water is employed both as the motive fluid fordriving the belt and for washing the filter.

This improvement is accomplished by using a simple, low-cost,water-driven turbine, such as the type commonly employed in lawnsprinkler devices, to both drive the belt and to direct its exhaustwater into washing relation with the belt.

In a preferred embodiment of this invention, an endless foraminous beltis trained over a pair of spaced-apart rollers to one of which theturbine shaft is drivingly connected, the other roller functioning as anidler roller. The exterior of the drive roller is provided withbristlelike projections which cooperate with the openings in the belt tofunction both as drive teeth to aid in advancing the belt and todisplace particulate matter which may collect in such openings in thebelt material and thereby aid the washing action of the water directedthrough the belt openings from the turbine exhaust.

The arrangement described thus provides an automatic self-cleaning airfilter which lends itself readily to numerous applications for filteringand cleaning air, as well as other gas streams, for humidity control andfor evaporative cooling.

In other modifications, the filtering and washing elements may besupplemented by drying elements employing air drawn from the cleaned airsystems or from external sources to remove excess moisture from the beltbefore it is returned to the main circulating system.

Other and more specific objects and advantages of this invention willbecome more readily apparent from the following detailed descriptionwhen read in conjunction with the accompanying drawing which illustratesseveral embodiments in accordance with this invention.

In the drawing:

FIG. 1 is a generally diagrammatic elevational view,

partly in section, illustrating the system in accordance with a basicembodiment of this invention;

FIGS. 2 and 3 are diagrammatic illustrations of modifications of theembodiment of FIG. 1;

FIG. 4 is a view generally similar to FIG. 1 to which is added a dryingstage employing system air as the drying medium;

FIG. 5 is a view similar to FIG. 4 but illustrating the employment ofoutside air as the drying medium;

FIG. 6 is a view, in perspective, of the basic filter drive and washelements of the device; and

FIG. 7 is a detail, on an enlarged scale, illustrative of the filterdrive and washing elements of the apparatus.

Referring first to the structure illustrated in FIGS. 1, 6 and 7, thebasic elements comprise an endless foraminous web or belt 10 of anysuitable form to be described hereinafter, which is trained over a driveroller 11 and an idler roller 12 supported for rotation on suitableshafts or trunnions 13 and 14, respectively, the rollers being disposedon opposite sides of an air duct D through which the upper and lowerruns 10a and 10b, respectively, of the belt move transversely withrespect to the direction of the air flow through the duct. A housing 15mounted to opposite sides of the duct encloses the roller and theportions of the filter belt which are outside the duct. The walls of theduct are provided with suitably spaced and shaped openings 16 to permitfree passage of the belt runs and each of the openings is sealed aboutthe belt surfaces by means of suitably arranged flexible sealing flaps17 of any suitable and generally conventional form adapted to permitready movement of the belt through the openings without substantial airleakage.

The belt is driven by means of a small Water-driven turbine 18 of anywell-known and generally used type such, for example, as is commonlyemployed for rotating or oscillating lawn sprinklers. The turbine issuitably mounted in housing 15 adjacent one end of drive roller 11 andbetween the belt runs. The turbine is provided with a water supplyconduit 19 and has the usual waterdriven power shaft 20 and a waterexhaust conduit 21 which is arranged to extend parallel to the driveroller and is provided with a plurality of spaced-apart dischargenozzles 22 which are disposed so as to direct water jets dischargingtherefrom toward the under surface of belt run 10a at approximately thejuncture of the upper belt run with the surface of drive roller 11, forpurposes to be described more fully hereinafter.

Shaft 20 is connected by a crank 23 through a connecting rod 24 to acrank 25 mounted to shaft 13, whereby rotation of shaft 20 may betransmitted to shaft 13 to rotate drive roller 11.

Belt 10 may be constructed of any suitable metallic or nonmetallicmaterial, or combination thereof, having openings or pores of therequisite size and shape best suited for the particular service in whichit is to be used. For example, the belt may be constructed of perforateor woven metal, or of plastic, fibreglass or any other suitable materialhaving perforations or openings 30 (FIG. 7) of any suitable shape, whichmay be round, square, elongate in the direction of the movement of thebelt, and of dimensions appropriate to filter out particulate materialto be removed from the air passing through the belt.

The exterior surface of drive roller 11 is provided with a coating ofradially projecting bristle-like elements 29 arranged and shaped toproject through openings 30 in the belt. These bristle-like elementsserve the dual functions of drive-teeth for transmitting the torsionalforce from the drive roller to the filter belt and to act as scavangingelements for displacing particulate matter, lint and the like from thebelt openings into the path of wash water ejecting from nozzles 22.

The bristle-like elements 29 are preferably constructed of non-metallicmaterials such as plastic or rubber compositions having a sufficientdegree of rigidity to perform the driving and cleaning functions notedabove. They may also be made of metal where the character of the filterbelt and temperature conditions warrant.

In its simplest application, where only air-filterlng and washing of thefilter belt are required, as illustrated in FIG. 1, water under pressurewill be directed through conduit 19 to turbine 18 to rotate shaft 20which will then drive roller 11. The rotation of the latter will,through friction as well as by direct engagement of elements 29 inopenings 30, drive belt 10 across the path of flow of the air stream induct D. The water exhausting through nozzles 22 will be dischargedoutwardly through openings 30 to aid in cleaning the belt of anyparticulate matter collected therein in passage through duct D. Elements29 will have at least initiated the dislodgment of particulate matterimmediately in advance of or simultaneously with the impingement of theexhaust water on the belt openings. The combination of dislodging actionof the bristlelike elements and the closely correlated washing action ofthe exhaust water assures elfective cleaning of the portion of the beltreturning to duct D as lower belt run 10a.

The exhaust wash water collecting in housing 15 after use will bedischarged therefrom through a drain pipe 31.

FIG. 2 illustrates a modification where additional washing of the filterbelt may be found desirable or necessary to clean the belt moreeffectively before it is returned to the air duct. In this case, waterjets 26, of any suitable and known design (one shown) are connected tosupply pipe 19 through a line 27 and have discharge nozzles 28 directedat the juncture of lower belt run 10b with idler roller 12 thusproviding additional washing of the belt.

FIG. 3 illustrates a further modification designed for increasing thedegree of air-cleaning and belt-washing to met particular conditions. Inthis modification the filter belt v10 is passed back and forth in aplurality of passes through duct D, the several passes of the filterbelt being trained over a plurality of suitably arranged idler rollers12 before returning to drive roller 11. Only one drive turbine 18 isemployed but each run of the belt as it leaves the duct is subjected toWashing by a water jet 26 located adjacent the related idler roller 12.

FIGS. 4 and illustrate modifications by which drying of the filter beltmay be effected to regulate humidit of the filtered and washed air.

In FIG. 4 the filter belt is extended in length to form an extension 32arranged to pass downwardly from drive roller 11 over an idler roller 33and thence upwardly over a guide roller 34 before passing back throughduct D to idler roller 12. Belt extension 32 and rollers 33 and 34 areenclosed Within a housing extension 35 positioned alongside duct D andseparated by means of a partition 36 from the portion of housing 15which encloses drive roller 11 and water turbine I18, hereinafter calledthe washing zone, the housing extension being referred to as the dryingsection. The wall of duct D between belt runs 102: and b is providedwith louver-controlled openings 37 through which filtered air afterpassing through upper belt run 10a is directed into housing extension 35between the belt runs housed therein. Additional louver-controlledopenings 38 in the wall of duct D below lower belt run 10b are arrangedto direct filtered air passing through lower belt 10b into and throughthe belt extensions in housing extension 35 from which the air will exitthrough louvered openings 39 in the outer wall of the housing extension.

Thus, a controlled portion of the air filtered by its passage throughbelt runs 10a and 10b may be directed through the extended sections ofthe belt leaving the washing zone in order to remove wash waterremaining on the belt and thereby control the humidity of the airpassing through the duct after leaving the filter area, I

The drying section heretofore described may be made to any suitabledimensions and with any desired number and arrangement of idler pulleysto regulate the dwell time of the belt under drying conditions prior toduct re-entry so as to control the moisture load in the main air streamto any extent desired.

FIG. 5 illustrates a modification of the arrangement shown in FIG. 4,differing therefrom in using outside air as the drying medium. In thismodification, a blower 40' mounted in housing extension 35 draws airfrom outside the housing through a suction line 41 and discharges it viaa discharge nozzle 42 through the portions of the belt runs passingthrough the housing extension between rollers 33 and 34. The drying airpassing through the belt will be discharged from the housing extensionthrough louvered openings 39.

If desired, the air going to blower 40 may be passed through a heater(not shown) if more rapid drying of the belt is desired.

It will be evident that the afore-described system lends itself readilyto numerous variations in addition to those illustrated and described.The movement and washing of the belt may be continuous or intermittent.For example, an arrangement such as shown in FIGS. 4 and 5 could betimed for intermittent operation wherein one-half of the total beltlength would be withdrawn from the air duct, passed through the cleaningchamber and moved into the drying chamber. Here, the cycle would bestopped and the belt held stationary until the belt was thoroughly dryand thereafter returned to the filter section and the cycle thenrepeated. Or, it may be found that for a specific installation only onecleaning cycle was required in a given period of time and intermittentoperation could be timed accordingly.

It will be evident that numerous other alterations and modifications maybe made in the details of the illustrative embodiments within the scopeof the appended claims but without departing from the spirit of thisinvention.

What I claim and desire to secure by Letters Patent is:

1. An air filter apparatus, comprising:

(a) an endless belt of a foraminous material movable transversely of thepath of flow of an enclosed air stream;

(b) said belt being trained over longitudinally spacedapart drive andidler rollers;

(c) a water-driven turbine having a driven shaft and a water exhaustconduit;

((1) means for supplying drive water to said turbine;

(e) means drivingly connecting said shaft to said drive roller; and

(f) means for directing exhaust water from said water exhaust conduitinto washing relation with said belt following passage thereof throughsaid air stream.

2. An air filter apparatus according to claim 1 wherein said driveroller carries bristle-type drive elements adapted to project throughopenings in said foraminous material.

3. An air filter apparatus according to claim 1 wherein saidlast-mentioned means includes:

(a) a header extending transversely beneath a belt run;

and

(b) a plurality of laterally spaced-apart discharge nozzles arranged onsaid header to direct exhaust water outwardly through the belt openingsadjacent the drive roller.

4. An air filter apparatus according to claim 1 including jet means fordirecting wash water through a portion of said belt adjacent said idlerroller.

5. An air filter apparatus according to claim 1 wherein said endlessbelt is trained over a plurality of additional idler rollers arranged onopposite sides of said enclosed air stream between said drive roller andthe firstmentioned idler roller, whereby to effect additional traversesof said air stream by said belt.

. 6. An air filter apparatus according to claim 5 includmg jet means fordirecting wash water through portions of said belt adjacent at leastsome of said additional idler rollers.

7. An air filter apparatus according to claim 1 including drying meansfor directing a stream of drying fluid through a portion of the washedbelt at a point along the path of its return to contact with said airstream.

8. An air filter apparatus according to claim 7 wherein said dryingfluid comprises air drawn from the enclosed air stream at a pointfollowing its passage through said belt.

9. An air filter apparatus according to claim 7 wherein said dryingfluid comprises air drawn from outside said enclosed air stream.

10. An air filter apparatus, comprising in combination with a ductenclosing the path of flow of an air stream:

(a) an endless belt of a foraminous material movable through the ducttransversely of the path of flow of said air stream;

(b) said belt being trained over a drive roller and an idler rollermounted on opposite sides of said duct;

(c) a housing enclosing said drive and idler rollers;

(d) a water-driven turbine having a driven shaft and a water exhaustconduit mounted in the housing adjacent said drive roller;

(e) means for supplying drive water to said turbine;

(f) means drivingly connecting said shaft to said drive roller;

( means in said housing for directing water from said water exhaustconduit into washing relation to said belt; and

(h) means for draining wash water from said housing.

References Cited UNITED STATES PATENTS 1,941,524 1/1934 Wittemeier eta1. 55-290 X FOREIGN PATENTS 491,861 9/1938 Great Britain 55-354 DENNISE. TALBERT, 111., Primary Examiner US. Cl. X.R.

